What is the first-line therapy for seborrheic dermatitis?

First-Line Treatment for Seborrheic Dermatitis

The most effective first-line treatment for seborrheic dermatitis combines topical antifungal medications (ketoconazole 2% or selenium sulfide) with low-potency topical corticosteroids for significant inflammation, alongside gentle skin care with non-soap cleansers and moisturizers. 1

Scalp Seborrheic Dermatitis

For scalp involvement, start with ketoconazole 2% shampoo, which achieves an 88% response rate after initial treatment. 1

• Apply ketoconazole 2% shampoo or cream to affected scalp areas twice daily for 4 weeks or until clinical clearing 2
• Shampoos, gels, solutions, or foams are preferred over ointments and creams for scalp treatment due to ease of application through hair 1
• Alternative: selenium sulfide shampoo applied twice weekly for 2 weeks, then at less frequent intervals (weekly to every 3-4 weeks) for maintenance 3
• For thick, scaly plaques, coal tar preparations (1% strength preferred) can reduce inflammation and scaling 1
• If significant inflammation persists, add clobetasol propionate 0.05% shampoo twice weekly for superior efficacy 1

Facial Seborrheic Dermatitis

For facial involvement, apply ketoconazole 2% cream twice daily for 4 weeks, combined with hydrocortisone 1% cream for prominent erythema. 1, 2

Critical Facial Treatment Principles:

• Avoid all alcohol-containing preparations on the face—they significantly worsen dryness and trigger flares 1
• Use only low-potency corticosteroids (hydrocortisone 1% or prednicarbate 0.02%) on facial skin 1
• Limit corticosteroid use to 2-4 weeks maximum on the face due to high risk of skin atrophy, telangiectasia, and tachyphylaxis 1
• Never use medium- or high-potency steroids (triamcinolone, clobetasol, mometasone) on facial skin—they cause unacceptable adverse effects 1

Essential Supportive Facial Care:

• Use mild, pH-neutral (pH 5) non-soap cleansers or dispersible creams as soap substitutes 1
• Apply fragrance-free moisturizers containing urea (≈10%) or glycerin to damp skin immediately after bathing 1
• Avoid perfumes, deodorants, harsh soaps, and greasy/occlusive products that promote folliculitis 1
• Apply hypoallergenic sunscreen daily (SPF 30+, zinc oxide or titanium dioxide) 1

Body Seborrheic Dermatitis

• Apply ketoconazole 2% cream once daily to affected areas for 2 weeks 2
• For significant erythema, add hydrocortisone 1% or prednicarbate 0.02% cream for limited periods (2-4 weeks maximum) 1
• Apply emollients after bathing to provide a surface lipid film that prevents water loss 1

Second-Line Options for Inadequate Response

If no improvement after 4 weeks of ketoconazole treatment, consider topical calcineurin inhibitors (tacrolimus or pimecrolimus) for facial involvement or prolonged use beyond 4 weeks. 1, 4

• Topical calcineurin inhibitors are particularly useful where corticosteroids are unsuitable or for maintenance therapy 1
• For recalcitrant cases not responding to topical therapy, narrowband UVB phototherapy has shown efficacy 1
• Severe or widespread cases may require oral antifungals: itraconazole 200 mg/day for first week of month, terbinafine 250 mg/day for 4-6 weeks, or fluconazole 50 mg/day for 2 weeks 5

Adjunctive Symptomatic Management

• For moderate to severe pruritus, add oral antihistamines (cetirizina, loratadina, fexofenadina) 1
• Topical polidocanol-containing lotions provide additional relief for itching 1
• Salicylic acid 0.5-2% lotion can be applied once daily for keratolytic effect, gradually increasing frequency if tolerated 1

Common Pitfalls to Avoid

• Do not undertreat due to fear of corticosteroid side effects—use appropriate potency for adequate duration, then taper 1
• Avoid long-term corticosteroid use, especially on the face, due to risk of skin atrophy and tachyphylaxis 1
• Avoid neomycin in topical preparations due to high sensitization rates (13-30%) 1
• Do not use non-sedating antihistamines—they provide no benefit in seborrheic dermatitis 1
• Avoid hot water and harsh soaps that strip natural skin lipids 1

Monitoring for Complications

• Watch for secondary bacterial infection (crusting, weeping, pustules) suggesting Staphylococcus aureus—treat with oral flucloxacillin 1
• Look for grouped, punched-out erosions suggesting herpes simplex superinfection—treat immediately with oral acyclovir 1

When to Refer to Dermatology

Refer if diagnostic uncertainty exists, failure to respond after 4 weeks of appropriate first-line therapy, recurrent severe flares despite optimal maintenance, or need for second-line treatments. 1